1051 Merope is a dark Alauda

asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

from the outermost region of the asteroid belt, approximately in diameter. It was discovered on 16 September 1925, by German astronomer

Karl Reinmuth Karl Wilhelm Reinmuth (4 April 1892 in Heidelberg – 6 May 1979 in Heidelberg) was a German astronomer and a prolific discoverer of 395 minor planets. Scientific career From 1912 to 1957, Reinmuth was working as an astronomer at the Lande ...

at the

Heidelberg-Königstuhl State Observatory Heidelberg-Königstuhl State Observatory (german: Landessternwarte Heidelberg-Königstuhl) is a historic astronomical observatory located near the summit of the Königstuhl hill in the city of Heidelberg in Germany. The predecessor of the curre ...

in Heidelberg, Germany, and given the provisional designation . Reinmuth named it after the nymph Merope from Greek mythology. The asteroid has a

rotation period The rotation period of a celestial object (e.g., star, gas giant, planet, moon, asteroid) may refer to its sidereal rotation period, i.e. the time that the object takes to complete a single revolution around its axis of rotation relative to the ...

of 27.2 hours.

Orbit and classification

''Merope'' is a member of the Alauda family (), a large

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

of carbonaceous asteroids and named after its parent body,

702 Alauda 702 Alauda , provisional designation , is a carbonaceous asteroid and binary system from the outer asteroid belt, approximately 190 kilometers in diameter. It is the parent body of the Alauda family. Discovered in 1910 by German astronomer Joseph ...

. It orbits the Sun in the outermost asteroid belt at a distance of 2.9–3.5 AU once every 5 years and 9 months (2,105 days;

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...

of 3.21 AU). Its orbit has an eccentricity of 0.10 and an

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a Plane of reference, reference plane and the orbital plane or Axis of rotation, axis of direction of the orbiting object ...

of 24 ° with respect to the ecliptic. The asteroid was first observed as at Taunton Observatory in October 1908. The body's

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

begins at Heidelberg in October 1925, or three weeks after its official discovery observation.

Physical characteristics

''Merope'' has been characterized as a primitive

P-type asteroid P-type asteroids are asteroids that have low albedo and a featureless reddish spectrum. It has been suggested that they have a composition of organic rich silicates, carbon and anhydrous silicates, possibly with water ice in their interior. P-type ...

by the

Wide-field Infrared Survey Explorer Wide-field Infrared Survey Explorer (WISE, observatory code C51, Explorer 92 and SMEX-6) is a NASA infrared astronomy space telescope in the Explorers Program. It was launched in December 2009, and placed in hibernation mode in February 2011, ...

(WISE), and as a common carbonaceous C-type asteroid by Pan-STARRS photometric survey.

Rotation period

In March 2009, a rotational lightcurve of ''Merope'' was obtained from photometric observations by astronomers at the Oakley Southern Sky Observatory in Australia. Lightcurve analysis gave a

of 27.2 hours with a brightness variation of 0.20 magnitude (). In October 2012, astronomers at the

Palomar Transient Factory The Palomar Transient Factory (PTF, obs. code: I41), was an astronomical survey using a wide-field survey camera designed to search for optical transient and variable sources such as variable stars, supernovae, asteroids and comets. The projec ...

in California measured a period 13.717 hours with an amplitude of 0.11 magnitude in the R-band (), which seems to be an alternative period solution (1:2 alias) of what the Australian astronomers had previously measured. Previous observations by Gino Farroni and by Federico Manzini from 2004 and 2005, respectively, have been provisional and of poor quality ().

Diameter and albedo

According to the surveys carried out by the Infrared Astronomical Satellite

IRAS The Infrared Astronomical Satellite (Dutch: ''Infrarood Astronomische Satelliet'') (IRAS) was the first space telescope to perform a survey of the entire night sky at infrared wavelengths. Launched on 25 January 1983, its mission lasted ten mo ...

, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, ''Merope'' measures between 60.439 and 74.36 kilometers in diameter and its surface has an

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

between 0.03 and 0.053. The ''Collaborative Asteroid Lightcurve Link'' derives an albedo of 0.0358 and a diameter of 67.11 kilometers based on an

absolute magnitude Absolute magnitude () is a measure of the luminosity of a celestial object on an inverse Logarithmic scale, logarithmic Magnitude (astronomy), astronomical magnitude scale. An object's absolute magnitude is defined to be equal to the apparent mag ...

of 10.1.

Naming

This

minor planet According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor ...

was named after the nymph Merope from

Greek mythology A major branch of classical mythology, Greek mythology is the body of myths originally told by the Ancient Greece, ancient Greeks, and a genre of Ancient Greek folklore. These stories concern the Cosmogony, origin and Cosmology#Metaphysical co ...

. She is one of the seven

Pleiades The Pleiades (), also known as The Seven Sisters, Messier 45 and other names by different cultures, is an asterism and an open star cluster containing middle-aged, hot B-type stars in the north-west of the constellation Taurus. At a distance of ...

, daughters of the Titan

Atlas An atlas is a collection of maps; it is typically a bundle of maps of Earth or of a region of Earth. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats. In addition to presenting geographic ...

and the sea-nymph Pleione (). The star Merope in the

star cluster is named for the same.

References

External links

Asteroid Lightcurve Database (LCDB)
query form

)
Dictionary of Minor Planet Names
Google books

– Observatoire de Genève, Raoul Behrend

– Minor Planet Center * * {{DEFAULTSORT:Merope 001051 Discoveries by Karl Wilhelm Reinmuth Named minor planets 19250916